Concentrator



NOV. 7, 1944. 5, uc 2,361,927

CONCENTRATOR Filed Oct. 29, 1942 {Sheets-Sheet 1 52 a a: a

Aft

Nov. 7, '1944.

4 Sheets-Sheet 2 IITTK Nov. 7, 1944. R. s. BUCKMAN CONCENTRATOR FiledOct. 29, 1942 4 Sheets-Sheet 4 'j'n v @1111 r R. 5. Buck ma :4 r

Patented Nov. 7, 1944 CONCENTRATOR Ronald Sydney Buckman, Kimberley,British Columbia, Canada, assignor to The Consolidated Mining andsmelting Company of Canada, Limited, Montreal, Quebec, Canada, a companyof Canada Application October 29, 1942, Serial No. 463,842

9 Claims.

This invention relates to a method and apparatus for concentrating andseparately recovering the heavier ingredients or values of an ore pulp.

-In the treatment of mineral ores for the separation and recovery of themetal values therefrom, concentrating apparatus is commonly used bymeans of which the heavier ingredients or values in an ore pulp areseparated from the lighter gangue material or tailings. Concentratingapparatus may comprise a plurality of superposed decks or tablestiltably mounted in a frame. Ore pulp is fed to the decks at one endthereof for a period of time, during which the heavy ingredients orvalues are retained on the decks and the lighter gangue material ortailings pass over the decks and are discharged from the opposite endsthereof. At the termination of the feeding period, the decks are tiltedat a relatively sharp vertical angle and the values are washed therefromwith water and separately collected.

Oneof the difficulties in the operation of existing concentratingapparatus is the tendency of the heavier ingredients or values containedin the ore pulp to settle out during the time interval the decks are inconcentrates discharging position and the flow of ore pulp thereto isstopped. As a result, the ore pulp fed to the decks is not of uniformconsistency and this lack of uniformity has an adverse effect on theconcentrating efliciency and the rate of treatment of the ore pulp isaffected accordingly.

One ofthe principal objects of the presentinvention is to provide amethod and apparatus whereby the ore pulp is continuously circulated ata substantially uniform rate of flow from a source of supply through adistributor vessel in communication with one or more concentrator units.During the period the decks of the concentrator unit are in .theirconcentrates discharging position, the ore pulp passing through thedistributor vessel is returned to the source of supply withoutrestriction of the rate of flow, whereby the heavier ingredients orvalues are given no opportunity to settle out and the ore pulp isconstantly of a substantially uniform consistency and can be fed to thetables at a uniform rate with high concentrating efliciency.

A further object of the present invention is to provide an operatingmechanism for a concentrator unit, which -is synchronized with thedistribution of the pulp feed from a centrally located distributorvessel by means of which a plurality of concentrator units can beoperated in multiple from a single driving unit, each unit receiving thesame volume of ore pulp of uniform consistency and the pulp feeding andconcentrates. discharging periods being predeterminable to treat themaximum volume of ore pulp and to obtain the maximum concentratingefficiency therefrom.

A further object of the invention is to provide an ore pulp distributorvessel in which the continuous flow of Ore pulp therethrough and itsdistribution to the respective concentrator units therefrom and thereturn of a portion of the ore pulp to the source of supply are effectedby a relatively simple arrangement of parts.

A still further object ofthe invention is to provide, in co-operationwith the distributor vessel, a relatively simple deflector element whichcollects, in sequence, the portion of the ore pulp flowing to eachconcentrator unit during the time interval that unit is in concentratesdischarging position, and returns that portion of the ore pulp withoutinterruption to the source of supply from which ore pulp is returned tothe distributor vessel without restriction in the rate of circulation.

The objects of the invention are attained by continuously circulating anore pulp at a substantially uniiorm' rate through a distributor vesselin communication with one or more concentrator units. The ore pulp ispassed to each concentrator unit for a predetermined time interval atthe termination of which it is deflected from each unit, in sequence,for a further predetermined time interval. The. deflected ore'pulp isreturned to the distributor vessel without restriction in the rate offlow into or from the distributor vessel.

The apparatus involved in the present invention includes a verticallydisposed distributor vessel having a plurality of open outlets in thebottom thereof, each open outlet being in communication with aconcentrator unit. Ore pulp is fed into the distributor vessel and isdischarged from the vessel through the said open outlets at asubstantially uniform rate of flow. Rotating'means are provided belowthe open outlets for diverting in sequence the ore pulp feed passingthrough each of. the said outlets and -means are providedforcontinuously returning Figure 1 is a cross-sectional side elevationof the concentrator units incorporating the improvements of the presentinvention;

Figure 2 is a cross-sectional front elevation of a series ofconcentrator units;

Figure 3 is an enlarged cross-sectional side elevation of thedistributor;

Figure 4 is a plan view of the bottom of the ore pulp distributor;

Figure 5 is a top plan view taken along the line 5-5, Figure 3;

Figure 6 is an enlarged detail view of a concentrator unit actuatingarrangement; and

Figure 7 is a plan view of the blanket material used on the decks ofeach concentrator unit.

Like reference numerals refer to like parts throughout the specificationand drawings.

The multiple unit concentrator of the present invention comprises, ingeneral, a centrally located distributo into which ore pulp ofsubstantially uniform consistency is constantly fed and from which it iscontinuously discharged at a relatively uniform rate of speed at whichthe settling out of the heavier ingredients or metal values issubstantially avoided: a plurality of concentrator units fed from thedistributor; and actuating mechanism for each concentrator unitsynchronized with the distribution of the ore pulp in such a manner thatore pulp is fed to each unit for a predetermined period of time andatthe termination of which the decks of each unit are tilted toconcentrates discharging position for a predetermined period of time,during which latter period the orepulp feed to each unit in which thedecks are in concentrates discharging position is diverted and returnedto a sump without change in the normal rate of ore pulp circulation.

Referring to Figure 1 of the drawings, the ore pulp feed flowing throughthe launder 3| is received in the sump 32 from which it is pumped, by apump 33, through pipe line 33a into a distributor 80 which is locatedabove and centrally of the series of concentrator units. The ore pulpflows by gravity from distributor B0 to the respective concentratorunits.

The distributor 80 is formed with a series of openings 8| spaced aroundthe periphery of the lower end thereof. An annular trough 95 surroundsthe lower end of the distributor. The trough 95 is provided with outletspouts 35, spaced preferably at equal intervals around the periphery ofthe bottom. The. number of spouts 35 corresponds to the number ofconcentrator units fed from the distributor. An outlet opening BI ispreferably'formed in the wall of the distributor immediately above eachspout 35.

A hopper 36, in which is collected the ore pulp feed to eachconcentrator unit, is located below each spout 35. Each hopper 36 isprovided with an outlet pipe 31 which feeds the pulp into a drum 38,from which it is'fed into the. deck feed boxes 40 through the feed lines39.

A housing 34 encloses the distributor 80, the trough 95 and the hoppers36. The outlet pipes 31 extendthrtiugh the wall of the housing 34.

A driven shaft 4| enclosed in casing 42, is verasonozw The shaft 45 isdriven from the motor 46 mounted on the top of the housing 34 through achain or V-belt drive 41 which extends to the motor pulley 48.

An open-top, sector-shaped deflector 49 is mounted on the lower end ofthe shaft below the bottom of the distributor 80, being interposedbetween the spouts 35 and the feed hoppers 36. The deflector 49 isrotatable with the shaft 4|.

.The deflector 49 is preferably of sector shape through into the line 5|through which the ore pulp is returned to the sump.

Each concentrator unit comprises a plurality of superposed, tiltabledecks mounted in a frame. For the 'purpose of illustrating the ore pulpfeeding and concentrates discharging positions of the decks, two unitsare illustrated in Figure 1, the decks in the unit indicated bythenumeral I being shown in the concentrates washing and dischargingposition and the decks in the unit indicated by the numeral 2 beingshown in pulp feeding and tailings discharging position.

Each unit comprises a plurality of superposed decks or tables 3 mountedin a frame. A standard or column 4 extends from the bottom to the top ofthe frame. A pivotal bar 5, located preferably centrally of thelongitudinal axis of each deck, extends transversely across theunderside of the deck. Each deck is carried on and movable with itspivotal bar 5. Each pivotal bar 5 is pivotably secured to the standard4.

The decks 3 of each unit are moved to their respective pulp feeding andconcentrates discharging positions by a lever B, one end of which ispivotably secured to the block 8 mounted on the top of the frame, andthe opposite end of which is connected to the rod III which extendsdownwardly into the frame. A crank I extends from the rod ID to eachpivotal bar 5. A cam follower I2 is mounted on the lever 8, between theblock 9 and the rod I0. Cam follower I2 is in constant engagement withthe periphery of cam |3 which is mounted on and rotatable with cam shaft4. Cam 3 is designed with an outwardly extending projection |3a whichextends a predetermined distance around its periphery.

The water system comprises a spray pipe 14 which extends transverselyacross the end of each deck remote from the ore pulp feed andconcentrates discharge end. Each spray pipe 14 is connected, by means ofa branch line 13, to the main distribution line or header 12. A valve1|, preferably of the plunger-operated, quick-opening, spring-closedtype is interposed between the water supply line 10 and the distributionline or header 12,

The valve H is opened by a projection 16 extending outwardly from theperiphery of cam 15. Cam 15 is mounted on and rotatable with shaft 4 andthe projection 16 is designed to open and to hold in open position thevalve 1| for a predetermined period during each complete rotation of cam15.

Cam shaft [4 is driven from shaft 45 through a chain 11 or otherpositive means.

fed to the tables with the maximum rate of feed from which a highconcentrating efliciency can be realized.

As an example of the operation of the app'aratus, it may be assumed, forpurposes of illustration, that a complete cycle of operations for eachunit of the apparatus. can be eifected in five minutes-four minutestaken in feeding ore pulp to the tables and one minute fordischargingthe concentrates from the tables. The various driving gears are,therefore, designed to drive shafts 4| and Il one complete revolution infive minutes. The projection I30 is designed to extend one-fifth of thedistance around the periphery of cam ll. During the time in which camfollower I2 is in contact with projection Ha,

that is. one minute, the tables I are tilted to discharging position,washed with water, and returned to feeding position. Projection 16 oncam II is designed to actuate valve II when the .tables are indischarging position, thereby reend of the decks. Each deck is coveredby a rubher-like cloth material of grid-like pattern in which the raisedgrids 90 extend transversely of the deck as illustrated in Figure '7..The heavier ingredients or values of the ore pulp flowing over thedecks are retained on the grid-like deck covering between the grids 90,and the lighter .ingredients, or tailings, flow downwardly over the gridlines and are discharged into tailings launder 6.

When the decks have been receiving feed for a predetermined time, therotation of shaft 4| brings the deflector under the spout 3i, and thefeed to that particular unit is shut ofl. The decks of that particularunit are then tilted to their concentrates discharging position asillustrated in Figure 1 by the position of the decks in the unitindicated by the numeral I. In this unit,

' the decks are tilted to a relatively sharp angle,

leasing a flow ofwater over the tables to wash the concentrates intoconcentrates launder l.

The positions of deflector 49 on shaft ll and of projections lid and Iton cams l3 and 15 for example'about 48, towards the concentrates launderI by the actionof cam follower l2 rising on projection I 3a which raiseslever B. When the decks are tilted, projection I6 actuates valve 1| intoopen position and the flowof water to the spray pipes 14 washes theconcentrates from the decks 3 into the concentrates launder 1. 0ncompletion of the washing and discharging period, as terminated by thefurther rotation'of the cams I5 and 13, the decks are returned to theirfeeding position and the flow of pulp to the decks is resumed by furtherrotation of shaft ll which carries deflector 49 clear of the spout 35.

An apparatus comprising five concentrator units with a period of fiveminutes to effect a respectively are so arranged, in the operation of aparticular concentrator unit, that when the deflector moves under spout35, thereby shutting off the flow of material to hopper 36 and divertingthat portion of the feed to the sump 32. the lever I is raised by theaction of cam follower I2 contacting projection l3a. and, when thetables have been tilted to discharging position, valve H is opened bythe action of projection 16 coming into contact with the valve openinplunger.

During the period that the flow of ore pulp to a unit is shut off, thereis no decrease in the volume of ore pulp flowing through thedistributor; that portion of the ore pulp which would otherwise be fedto the unitwhich is shut off, is

diverted, by the deflector, to the feed sump, from which the ore pulp ispumped to the distributor vessel 80. By maintaining the'circulation ofva constant volume or ore pulp through the distribcomplete cycle ofoperations will serve todllustrate an embodiment of the invention. Inthis embodiment, the distributor is equipped with five outlet spouts,each supplying feed to a correspondingconcentrator unit. The rotation ofthe deflector is regulated. to complete one rotation in five minutes. Asit rotates, the deflector diverts the flow from each spout, in turn, fOrone minute. During the one-minute interval that the feed to aconcentrator unit is shut ofl, the decks of that unit are tilted,washed, and returned to feeding position. When the deflector hascompleted one rotation, each of the five units, in turn, will have beendischarged. At any one period of the cycle. four concentrator units willbe receiving feed and one unit will be discharging concentrates. eachunit discharging, in sequence, once every five minutes.

The apparatus has been described with reference to five concentratorunits and a distributor utor; no opportunity is afforded for any of theingredients of the pulp to segregate or settle in any part of thedistributor unit. When the feed is cut oil? from a concentrator unit,the remaining feed material in the'hopper, drum and feed lines of theunit, drains onto the concentrator decks by gravity. As there is noaccumulation of pulp in any part of the distributor system, a feed ofuniform consistency is supplied to the concentrator decks, anddifficulties dueto plugging of pipe lines and conduits are avoided.

The cycle of the operation of the apparatus may be considered ascommencing with the decks example. a series of ten concentrator unitsmay be su plied from 'a 'distributor which has two deflectors: in thiscase, there would always be in feeding position, as illustrated inFigure 1 by the unit indicated by the numeral 2. In this position, afeed box 4. is located to distribute ore pulp substantially uniformlyacross the width of one end of each deck. The periphery of cam II isdesigned to cause lever B to hold the tables at a slight downward angletowards the opposite two units discharging concentrates while eightunits are receiving feed.

The time required for a complete cycle may be varied with the rate ofcirculation of the ore pulp. the volume of pulp to be treated and the lcomposition of the pulp. The feeding and con-- cent-rates dischargeperiods are determined to give the maximum concentrating efilciency andthe mechanism of the apparatus is adjusted accordingly.

It has been found that the present apparatus is particularly adaptablefor the concentration of values in a finely divided ore pulp. Thecontlnuous circulation of the ore pulp during the complete cycle ofoperations prevents any settling out of the heavier ingredients orvalues in any part of the system and ensures a substantially uniformrate of feed of ore pulp of uniform consistency to the concentratingtables which permits a rapid rate of treatment with high concentratingefliciency. The timing of each operation is positive in its action andcan be controlled precisely to attain the most satisfactory results. Inaddition, a number of units can be driven from a single driving anddistributing arrangement and the various operations of each unitpositively controlled to attain the maximum results without interferencewith the sequence of operations of any of the other units.

The distributor device of the present invention can be incorporated intoapparatus other than the concentrator units described and illustratedherein. It can be used effectively with other .forms of apparatus wherea slurry or ore pulp is to be divided into several equal streams. suchas for supplying feed to a series of filters or centrifuges. These andother embodiments of the invention may become apparent to others skilledin the art in the light of the teachings herein without departing fromthe scope of the appended claims.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is:

' feed hopper below each open outlet to feed ore pulp to the decks of aconcentrator unit in communication therewith, and constantly rotatingmeans between said open outlets and said feed hoppers for interruptingin sequence the flow of feed to each feed hopper, and'means for tiltingthe decks of each concentrator unit to a discharging position during theinterval the feed thereto is interrupted and for returning said decks toa feed receiving position at the termition of said interval.

2. A concentratorapparatus comprising a plurality of concentrator units,each unit comprising a frame having superposed decks tiltable in avertical plane mounted therein, a centrallylocated vertically-disposedfeed distributor having a plurality of open outlets in the bottomthereof, the number of open outlets. corresponding to the number ofconcentrator units in said apparatus, means for continuously feeding orepulp from a source of supply into said feed distributor, a feed hopperbelow each open outlet to feed ore pulp to the decks of a concentratorunit in communication therewith, and constantly rotating means betweensaid open, outlets and said feed hoppers for diverting from each ofsaidfeedhoppers in sequence the feed flowing through each of said openoutlets, and means synchronized with said rotating means for holdingthedecks of each unit in a feed receiving position during the period ofcommunication between the feed hopper thereof and the feed distributorand for tilting the'decks of each unit to a discharging positionduringthe period the.

rotating means interrupts communication between the feed hopper thereofand the feed distributor. a

3. A concentrator apparatus comprising a plurality of concentratorunits, each unit comprising a frame having superposed decks tiltable ina. vertical plane mounted therein, a centrallylocated,vertically-disposed feed distributor having a plurality of open outletsin the bottom thereof, the number of open outlets corresponding to thenumber of concentrator units included in said apparatus, means forcontinuously feeding ore pulp from a source of supply into said feeddistributor, a feed hopper below each open outlet to feed ore pulp tothe decks of a concentrator unit in communication therewith, a verticalrotatable shaft extending through said distributor, a sector-shapeddeflector element mounted on said shaft below said open outlets, saiddeflector element passing under each of said open outlets in sequenceduring the rotation of said shaft, and a rotatable cam shaftsynchronized with the rotation of said rotatable shaft, and a cammounted on said cam shaft, and lever means actuated by said cam formoving said decks to their pulp feeding and concentrates dischargingpositions.

4. Apparatus for the treatment of ore pulp and the like which comprisesa feed distributor distributor having a plurality of open outlets in thebottom thereof, each open outlet being in communication with anintermittently charged concentrator unit, means for continuously feedingore pulp from a source of supply into said feed distributor, androtating means for diverting in sequence the feed passing through eachof said outlets and means for continuously returning said diverted pulpfeed to said feed distributor through said source of supply, wherebycontinuous circulation of the diverted portions of the feed material ismaintained.

6. In a mechanical ore concentrator, a vertically disposed feeddistributor having a plurality of open outlets in the bottom thereof,each open outlet being in communication with an intermittently chargedconcentrator unit, means for continuously feeding ore pulp from a sourceof supply into said feed distributor, a vertical rotatable shaftextending through said feed distributor, a sector-shaped deflectorelement mounted on said shaft below said open outlets, said defiectorelement passing under each of said open outlets in sequence during therotationof said shaft, and means communicating with said deflectorelement for continuously returning de- 7. A concentrator apparatuscomprising a concentrator unit, the concentrator unit comprising a framehaving at least one deck tiltable in a vertical plane mounted therein, avertically disposed feed distributor having an open outlet in the bottomthereof, means for continuously open outlet to feed ore pulp to thedecks of the concentrator unit, and constantly rotating means betweenthe open outlet and the feed hopper for interrupting the flow of feed tosaid feed hop er, and means for tilting the decks to a dischargingposition during the interval the feed thereto is interrupted and forreturning the decks to a feed receiving, position at the termip of openoutlets corresponding to the number of concentrator units in saidapparatus, means for continuously feeding ore pulp from a source ofsupply into said feed distributor, a feed hopper below each open outletto feed ore pulp to the decks of a concentrator unit in communicationtherewith, and constantly rotating means between said open outlets andsaid feed hoppers for diverting from each of said feed hoppers insequence the feed flowing through each of said open outlets, and meanssynchronized with said rotating means for holding the decks of each unitin a feed receiving position during the period of communication betweenthe feed hopper thereof and the feed distributor and for tilting thedecks of each unit to a discharging position during the period therotating means interrupts communication between the feed hopper thereofand the feed distributor, and including means for washing the decksduring the period they are tilted to a discharging position, and meansfor separately recovering the material washed therefrom. f

. 9. In a process for concentrating the heavier ingredients 'or valuesof an ore pulp in a plurality of intermittently charged concentratorunits, the improvement which comprises the steps of continuouslycirculating ore pulp at a substantially uniform rate, dividing the orepulp into a plurality of separate streams, the number of streamscorresponding to the number of concentrator units, distributing eachstream to its respective concentrator unit for a predeter' .mined timeinterval, diverting the'streams, in

sequence, from their respective concentrator units for a predeterminedtime interval, and returning each diverted stream to the continuouslycirculating ore pulp for distribution there- RONALD SYDNEY BUCKMAN.

